Type: report

Article abstract: In 1996, 3330-3392 pairs of the endangered California least tern (Sterna antillarum nested at 35 sites along the coast of California. This 29% increase in breeding population size over 1995 resumes the predominant pattern since 1987 of exponential growth of the statewide population. Fledgling-to-pair ratios at most sites increased relative to those in 1995, and terns nesting at several sites in 1996 were very successful. However, heavy predation at many San Diego County sites (including a majority of those with high pair numbers) and a local food shortage at Venice Beach compromised statewide fledgling production somewhat. Approximately 1981-2120 young terns fledged across the State, a record high and almost twice the number fledged in 1995; statewide F/P = 0.58-0.64. Most sites experienced increases over 1995 in the number of breeding pairs present, and several sites attracted more than 200 pairs. In 1996, 58% of the statewide papulation bred at only seven sites (NAS Alameda, Venice Beach, Huntington Beach, Santa Margarita River/North Beach, Mission Bay/FAA Island and Mariner's Point, Delta Beach/North), with the balance being distributed pretty evenly throughout the rest of the State. Almost half of the fledglings produced in the State came from only four sites; 45% of all potential new breeders produced this year fledged from NAS Alameda, Huntington Beach, Santa Margarita River/North Beach, and Delta Beach/North.